Icy Dock should design a 5.25" 4-in-1 enclosure with a backplane compatible with 4 x 2.5" NVMe SSDs. This will allow users of Highpoint's new RocketRAID 3840A NVMe RAID controller to connect 4 x U.2 cables directly to that backplane.
This CAD drawing comes very close, but I believe it was designed for 6 or 8 x 2.5" SSDs:
And, it needs 2 x 40mm fans (note that there are no holes to fasten fans in that CAD drawing).
Many users of Icy Dock's 4-in-1 enclosures for SATA SSDs will immediately appreciate a similar enclosure for 4 x 2.5" NVMe SSDs.
KEEP UP THE GOOD WORK!